Personalized photo products such as photobooks, greeting cards, and photo calendars often include many customizable features. Creating such an image-based product requires storing and presenting many variable objects by a computer device, and many, frequent user interactions at the computer user interface. A user interface that allows a user to edit multiple photobook pages can easily include thousands to tens of thousands variable components. The product design operations tend to require a lot of computation resources, which are often beyond the capabilities of many users' computers.
Performance is therefore a serious issue in highly interactive image-based product designs. Some users can experience very slow responses in displaying and refreshing after each user commanded component change. Sometimes, the user computer may be frozen under the heavy computation load of the design tasks. There is therefore a need to allow users to design image-based product in a more time responsive manner.